Showerhead



FIG. 1 is a perspective view taken from the top, rear _and right side of a showerhead showing my new design;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a front elevational view thereof; and

FIG.4 is a left side elevational view thereof. 

The ornamental design for a showerhead, substantially as shown and described. 